Strange facts about the eucalyptus

Strange facts about the eucalyptus

236 Notes and Comments. !j. F. I., Notes and Comments. T E S T S OF N E R N S T L A M P S F O R PUBLIC L I G H T I N G . At a recent m e e t i n g ...

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236

Notes and Comments.

!j. F. I.,

Notes and Comments. T E S T S OF N E R N S T L A M P S F O R PUBLIC L I G H T I N G . At a recent m e e t i n g of t h e British Institution of Electrical Engineers in London the results of the e x p e r i m e n t s with the Nernst electric light for public l i g h t i n g purposes were given. A mile of a street in H a c k n e y , one of the London suburbs, has been lighted by means of these lamps to obtain conclusive data regarding t h e i r durability, efficiency a n d suitability for such work. The main difficulty experienced was in connection with t h e starting of the light. This, however, was overcome by means of the a u t o m a t i e h e a t e r , which is put out of action directly the lamp lights up. But the result of this attachm e n t was not attended with absolute success, since considerable uncertainty exists in connection with the durability of t h e glow~.r. Some glowers lasted only I5 hours, while others r e m a i n e d efficient for 1,o7o hours, b u t the average life was 305 hours. This lack of uniformity constitutes one of t h e greatest objections to the wider utilization of the Nernst lamp for public lighting, despite its superiority in m a n y i m p o r t a n t features, a n d will necessitate considerable i m p r o v e m e n t before it is extensively adopted for i l l u m i n i n g the streets, with t h a t economy which is essential for such purposes. S T R A N G E FACTS ABOUT T H E E U C A L Y P T U S . Mr. D. E. Hutehins, of Cape Colony, who in I882, in conjunction with Sir A. Brandis, discovered t h e r e m a r k a b l e sun-power storage capacity of the eucalyptus, has again been drawing attention in Nature to this extraoadinary feature of t h e tree. According to Mr. Hutchins, a eueaiypt plantation in tropical mountains, such as in South Africa, u n d e r favorable circumstances, stores up about one per cent. of the solar energy received on the u n i t of area a n d it is considered m u c h cheaper in some parts of Cape Colony to plow up the land and plant a forest of quick-growing trees t h a n to import coal. I n 1882 Mr. H u t c h i n s and Sir A. Brandis, as t h e result of t h e i r experiments, discovered t h a t eucalypts planted on tropical m o u n t a i n s produce fuel at t h e rate of so t o n s - - d r y weight at 60 pounds per cubic f o o t - - p e r acre per year in perpetuity. T h e eucalypt plautation reproduces itself w h e n cut with. out f u r t h e r expense, and its dry timber, heavier t h a n coal, has an equal or a h i g h e r t h e r m a l power, bulk for bulk, t h a n coal. This result was obtained as a m e a s u r e m e n t of t h e m a x i m u m yield of Eucalyptusglobulus on the Nilgiris, Southern India. If a chance tree on a c h a n c e m o u n t a i n in a c h a n c e soil can produce the equivalent of 2o tons of coal per acre per year, it seems not unreasonable to suppose, Mr. H u t e h i n s suggests, t h a t by selection double this, or 4o tons, can be produced. A powerful sun, a heavy rainfall, and a very rapid forced growth are the essentials of such a production of wood fuel. A glance over the rainfall map of t h e world shows these conditions are fulfilled over about 8,ooo,oo.%ooo acres of its surface, which is between one-fourth and one-fifth of t h e total land surface of 35,2oo,ooo, ooo acres. One-half of this area u n d e r forest m i g h t thus yield t h e equivalent of I6O,OOO,OOO,OOO tons of

Sept., x9o3. ]

Notes and Comments.

237

coal yearly, which is more t h a n a88 times the world's present consumptiou of coal, assuming t h a t coal and eucalypt t i m b e r are of approximately equal heating power. On the basis of the actual forest yield of t h e p r e s e n t day, we have half of this, or t h e equivalent of 80,500,000,o.0 tons. In Germany, one fourth of the total area is u n d e r forest, and t a k i n g t h e G e r m a n standard of one-fourth forest, on t h e basis of t h e present m a x i m u m yield we should obtain 4o,25o,coo,ooo tons ; while if t h e m a x i m u m forest yield be converted to an average forest yield t h e r e would still remain a yearly product of 2o, x75,ooo,ooo tons, w h i c h is r a t h e r more t h a n t h i r t y times t h e world's present consumption of coal• T h u s it is seen t h a t t h e yield of firewood from t h e world's tropical and extra-tropical forests, wherever they are fully stocked and scientifically worked, will yield the equivalent of from 3o to 122 times the present consumption of coal, or even up to 243 times the present consumption, if by cultivation the present t i m b e r yield be doubled, as it m i g h t be without difficulty. THE ANCIENT RUINS OF RHODESIA. The remarkable ruins in South Africa, which by m a n y are boldly declared to be t h e remains of K i n g Solomon's mines, are fully described a n d illustrated in a recent work by R. N. Hall and W. G. Neal. No theories are offered for the presence of t h e ruins in savage lands. T h e authors, however, seem to incline to the opinion of Prof. Keaue, which is, in brief, t h a t " t h e ' gold of Ophir' came from Havilah (Rhodesia), a n d was worked and b r o u g h t t h e n c e first by the H i m y r r i t e s (Sabmans and Minmans), later by t h e Phoenicians. • . T h e n u m e r o u s objects of Semitic worship and t h e fragments of Himyaritic script found at Zimbaye and elsewhere south of t h e Zambesi leave no reasonable doubt t h a t the old gold-workings and associated m o n u m e n t s of this region are to be ascribed to the ancient Sabmaus of South Arabia and t h e i r Phcenician suecessors."--Scienlific American Supplement.

THE U S E OF P H O S P H O R U S M A T C H E S P R O H I B I T E D IN G E R M A N Y . The Reichstag has passed a bill forbidding t h e use of white or yellow phosphorus in m a t c h - m a k i n g after January I, 19o 3. T h e Secretary of the Interior, s p e a k i n g in favor of the bill, said t h a t phosphorus not only caused necrosis t h r e e or four years after a w o r k m a n had left a m a t c h factory, but that the disease thus contracted was h e r e d i t a r y , so t h a t whole families were affected• So subtle were the effects that the bones were fractured without t h e person at first b e i n g even aware of t h e fracture. The G o v e r n m e n t has reported favorably upon a m a t c h - m a n u f a c t u r i n g process said to be safe and

harmless.--Scientific American. ALCOHOL AS F U E L F O R I N T E R N A L COMBUSTION E N G I N E S . Tests made by C. W. Weiss, at the Mietz & Weiss E n g i n e Works, New York City, with Cuban a n d Brazilian cheap alcohol as fuel in their standard kerosene engine, have been reported as entirely satisfactory. The object was to substitute alcohol for ~erosene, the former b e i n g considerably cheaper and